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Mine takes about 2.

I would love to use Safari, IMO it's a much better browser. I just can't live without my AdBlock Plus.
 
After a reboot (which is rare) I find that Firefox will sometimes take anywhere from 5 ~ 10 bounces to start, which is an incredibly long time. I'm not sure what's going on when that happens, but after that initial launch, any subsequent launches take maybe 1 or 2 bounces; but most of the time it seems instantaneous.
 
3 on an Athlon64 3000+ with 1.5GB 333MHz single channel DDR loaded with a few apps 😉

... a friend told me.. (camino, not firefox)
 
4 on a new MBP, but with time for a few more after it stopped (before Firefox loaded).

1 after it has already loaded.
 
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